The Cannabis Grow Bible

The Cannabis Grow Bible

by Greg Green

The all-important 12/12

Most people never get good results or bud quantities from cannabis plants because they have never heard of 12/12.

12/12 is easy to explain. Cannabis plants grow outdoors naturally between the months of April to October/November. This means that towards the Sept/Oct/Nov dates the plants will be in flowering. During this time the days get shorter and the nights get longer. When this occurs the plant is under 12 hours of light and 12 hours of darkness. When this 12/12 PHOTOPERIOD occurs the plant is naturally stimulated to flower. If the 12/12 continues then the plant will produce its flowers. As long as 12/12 continues the flowers will grow larger and more plentiful. This is part of the cannabis plants evolution and how it has taught itself when to flower. Naturally as a grower we want lots of flowers so we need to put the plant through a light cycle of 12/12. This means that we must turn our lights on and off at these given ratios.

During pre-flowering you will either manually turn on your lights for 12 hours and turn off your light for 12 hours everyday or you will use an automatic timer. If your light comes with a timer set the timer to do this. Throughout the 12 hours of darkness it is best to keep your grow area as dark a possible. A small desk light at the other side of your room will cause your plant not to react properly to 12/12 which will result in continued vegetative growth. In fact any light that penetrates the darkness will stop your plants from flowering properly. That means that your grow room must be sealed to the point where it is completely light proof. If you want to learn how to do this perfectly then I suggest that you read up on ‘Photography Dark Rooms’, either on the Internet or in your local library.

Photographers use common items that can be bought in most hardware shops to make their film-processing rooms light tight. If you can replicate their ideas (basically a thick black screening around the door frames or any open light points) then you will have a great system for flowering plants in. I think most of you would have done this by now anyway if you listened and took the advice on covering your grow with either Mylar or white walls/boards. If you have prevented any light from leaking out, then you have prevented light from leaking in!

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